Safety-cap for boiler-plugs.



R. L. ETTENGER.

SAFETY CAP FOR BOILER PLUGS. APPLICATION FILED APR. 19, 1917- 1,83%,29?Patented Nova 27, 1917 ROBERT LEE ETT ENGEB, OF WASHINGTON, DISTRICT OFCOLUMBIA.

snnn'rr-car non BOILER-PLUGS.

Application filed April 19, 1917.

plug retaining and safety appliances used in connection with locomotiveboilers of any type wherein a plug cap is necessarily used in order toprevent the plugs from blowing out when undue force is concentratedagainst them. p

It has been the common-method to tap the fire box sheets and usethreaded screw plugs which engage the interiorly threaded holes in thesheets, but the action of the flue cleaner and ordinary corrosion of themetal soon decays the threads as well as the great wear on the threadsof both the plugs and boiler that necessarily follows from the frequencyof removal for washing out, which must be done in order to keep thetubes free from all deposits as explained above; so that failure toinspect or oversight in providing new plugs presents the danger of theirblowing out and a consequential damage. It is the purpose of thisinvention therefore to provide a means whereof a protecting cap may beapplied to prevent such occurrences and to provide further a simple andinexpensive device of the character referred to which may be used inconnection with any boiler to insure the retention of a plug within itssocket and which may be quickly and readily applied when needed;

The invention will first be hereinafter more particularly described,with reference to the accompanying drawings, which are to be taken as apart of this specification, and then pointed out in the claims at theend of the description.

In the drawings, Figure 1 represents a partial sectional view of theinterior of a locomotive boiler showing the location of the water tubesand washout plugs in association therewith, and my improved plugretaining safety device applied thereto;

Fig. 2 is a partial transverse sectional view of my specific improvementas adapted to be Specification of Letters Patent.

Patented Nov, 2'7, 1%"1.

Serial No. 163,150.

used with a plug having a projecting polygonal portion for applying anordinary wrench;

Fig. 3 is a front elevation of the bracket or plate member, inposition;v

Fig. 4 is a slight modification thereof;

Fig. 5 represents a slight modification of the bracket or plate memberas adapted to be used in connection with plugs which have a polygonalcavity instead of a nut-like portion' Fig. 6 is a sectional view similarto Fig. 2 of said modification;

Fig. 7 is also a transverse sectional view of another modification; and

Figs. 8 and 9 are further modifications of the bracket member.

In the drawings, in which the same reference letters are used to denotecorresponding parts in different views, the letter A may denote alocomotive boiler and a and a the back head and flue sheet thereof,respectively. The water tubes suitably mounted within said flue sheetand back sheet may be designated by of. The washout plugs 1 are commonlythreaded and screwed into suitably internally threaded passages or holesin the throat sheet and in the back head of the boiler and the saidpassages are preferably in a direct line with the ends of the watertubes to facilitate the washout process.

The plug 1 having the usual boiler-plate engaging threads 2 is providedon its head with a rounded shoulder 3 and a tool-engaging member orprojection 4 for turning the same. Surrounding the projection 4: andadapted to fit over the same but preferably spaced therefrom to allowperfect adjustment as hereinafter described, is the plug retainingmeans, in certain of the figures shown as a plate or cap '5 providedwith an aperture 6 preferably arranged centrally thereof and two lateralwings or arms 7. The central aperture 6 is provided peripherally thereofon one or both sides of the plate 5 with rounded seat or ball joint 8which is adapted to receive the similarly rounded shoulder 3 of the plugproper providing a ball joint against which the plate or cap bears.Obviously, the same universal adjustment or ball and socket is aifordedby having either the plug or plate rounded and the corresponding memberplain or not rounded. The lateral wings or arms 7 are provided withapertures 9 for engaging the studs 10 passing therethrough and threadedinto the boiler-plate on each side of the plug 1.

The plate or cap retaining devices may constructed without departingfrom the spirit and scope of my invention as set forth I take anydesired form such as riveted studs provided with discngageable heads orin fact any similar disengageable fastening means may be used.

In Fig. 4, the plate 5 is shown as having open sided apertures 11 forthe reception of the bolts or similar members 10, so that the plate canbe removed more speedily. Fig. 5 shows a similar arrangement of theplate illustrating also the central aperture. 12 as open sided.

Fig. 6 shows a modification of the projection 13 of the plug 1 and inthis case said projection is made round and interiorly formed to talrethe turning tool, as at 14:.

Fig. 7 illustrates a further embodiment of the invention, wherein theplug 1 is provided with a recessed portion 15, of any desired shape,herein shown as square and adapted to receive a correspondingly shapedstud 16 formed integral with the plate or cap. The plate is providedwith the before described fastening means.

Figs. 8 and 9 show the variant shapes 17 and 18 respectively of whichthe plate member may be made and is also shown as provided with theapertures for the plug projcction and fastening means.

It will of course be understood that various other forms of myimprovement may be ters Patent is:

1. In combination with a boiler-plate, a plug threaded thereinto andmeans detachably connected to said boiler-plate and adapted to preventsaid plug from blowing out due. to defective threaded connection;

said plug being provided with a rounded against said first 3. An art'icle of manufacture comprising a washout plug including a portion providedwith threads adapted to'ho'ld' the plug in a correspondingly threadedopening of a boiler-plate, said plug being also provided with a roundedportion adapted to contact with an auxiliary plug retaining member.

In testimony whereof I. aflix my signature in the presence'of twowitnesses.

ROBERT LEE ETTE GER.

WVitnesses i G. F. BRooKEs, '7 W J. CALNAN.

Copies of this patent may be obtained for five cents eachQby addressingt11e"Comm iss'ioner of Patents,

Washington, D. G.

